package Demo;

public class Rect extends Shape{
    @Override
    public void draw() {
        System.out.println("画一个矩形");
    }
}
abstract class A extends Shape{
       //这里必须重写draw方法  如果不想重写 需加abstract
   abstract void func();
}
class C extends A{


    @Override
    void func() {

    }

    @Override
    public void draw() {

    }
}